Surfactant-free synthesis and foaming of liquid blowing agent-containing activated carbon-nano/microparticulate polymer composites

Abstract

Exemplary embodiments of the present invention relate to polystyrene and/or thermoplastic polymer or polymer blend composite foam or a foamable polymeric material precursor, which contains activated carbon and/or at least one of 1-dimensional, 2-dimensional, and 3-dimensional nano/micro-materials in polystyrene and/or thermoplastic polymer and/or polymer blend matrix to carry a co-blowing agent such as water without using any surfactant-like molecules and/or polymers, having or adapted to have the properties of low density, high-R value, good mechanical properties, and fire retardance thereof. Exemplary embodiments of the present invention include various manufacturing methods that may be employed including, but not limited to, extrusion, batch molding, and injection molding. One example includes synthesis and CO 2 and water-based extruded foaming of such a material.

1 . A method for making a foamed polymer comprising:
 (a) preparing a foamable polymeric material precursor comprising:
 i. a polymeric material selected from the group consisting of polystyrene, thermoplastic polymers, and polymer blends thereof; 
 ii. a foaming facilitating material having affinity for a liquid, said foaming facilitating material comprised of material selected from the group consisting of activated carbon, charcoal, and 1-dimensional, 2-dimensional, and 3-dimensional nano/micro-materials and mixtures of two or more thereof, said foaming facilitating material adapted to contain said liquid in the absence of any surfactant-like molecules or polymers; 
 iii. a blowing agent; and 
 iv. said liquid; and 
   (b) preparing a foamed polymer from said foamable polymeric material precursor.   
     
     
         2 . A method according to  claim 1  wherein said polymeric material is polystyrene. 
     
     
         3 . A method according to  claim 1  wherein said polymeric material is selected from the group consisting of polystyrene/PMMA blends, polystyrene/PPO blends, thermoplastic polyolefin (TPO), polystyrene/high-impact polystyrene (HIPS) blends, PMMA, HIPS, polyvinyl chloride (PVC), maleic anhydrid modified PP (poly propyl methacrylate (PPMA)), polyethylene vinyl acetate (PEVA), acrylonitrile butadiene styrene (ABS), acrylic celluloid, cellulose acetate, ethylene-vinyl acetate (EVA), ethylene vinyl alcohol (EVAL), fluoroplastics (e.g., PTFE, FEP, PFA, CTFE, ECTFE, and ETFE), ionomers, Kydex (i.e., a trademarked acrylic/PVC alloy), liquid crystal polymer (LCP), polyacetal (e.g., POM and acetal), polyacrylates (acrylic), polyacrylonitrile (e.g., PAN and acrylonitrile), polyamide (e.g., PA and nylon), polyamide-imide (PAI), polyaryletherketone (e.g., PAEK and ketone), polybutadiene (PBD), polybutylene (PB), polybutylene terephthalate (PBT), polycaprolactone (PCL), polychlorotrifluoroethylene (PCTFE), polyethylene terephthalate (PET), polycyclohexylene dimethylene terephthalate (PCT), polycarbonate (PC), polyhydroxyalkanoates (PHAs), polyketone (PK), polyester, polyethylene (PE), polyetheretherketone (PEEK), polyetherimide (PEI), polyethersulfone (PES), polysulfone, polyethylene chlorinates (PEC), polyimide (PI), polylactic acid (PLA), polymethylpentene (PMP), polyphenylene oxide (PPO), polyphenylene sulfide (PPS), polyphthalamide (PPA), polypropylene (PP), polystyrene (PS), polysulfone (PSU), polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), spectralon, or a mixture thereof. 
     
     
         4 . A method according to  claim 1  wherein:
 said polymeric material is polystyrene; and 
 said foaming facilitating material comprises activated carbon. 
 
     
     
         5 . A method according to  claim 1  wherein said foaming facilitating material and said polymeric material are present in a weight ratio in the range of from about 20% to about 0.01%. 
     
     
         6 . A method according to  claim 1  wherein said foaming facilitating material comprises a 1-dimensional nano/micro-material selected from the group consisting of smectite clays, organoclays, nanographites, graphite, graphene, and graphene oxide. 
     
     
         7 . A method according to  claim 1  wherein said foaming facilitating material comprises a 2-dimensional nano/micro-material selected from the group consisting of carbon nanofibers, multi-wall carbon nanotubes, single wall carbon nanotubes, conducting polymer nanofibers and nanotubes, and polymer nanofibers/nanotubes. 
     
     
         8 . A method according to  claim 1  wherein said foaming facilitating material comprises a 3-dimensional nano/micro-material selected from the group consisting of quantum dots, polyoctahedralsilasesquioxanes (POSS), silica, and TiO 2 , ZnO, and Fe 3 O 4  nanoparticles. 
     
     
         9 . A method according to  claim 1  wherein said blowing agent is selected from the group consisting of CO 2 , N 2 , hydrofluorocarbons, fluorocarbons, and mixtures thereof. 
     
     
         10 . A method according to  claim 1  wherein said blowing agent is CO 2 . 
     
     
         11 . A method according to  claim 1  wherein said liquid is introduced into said polymeric material and said foaming facilitating material by exposing a solid combination of said polymeric material and said foaming facilitating material at a temperature below or above a softening temperature and at a pressure at or above atmospheric pressure for sufficient time to introduce said liquid into said foaming facilitating material. 
     
     
         12 . A method according to  claim 1  wherein said liquid is selected from the group consisting of hydrocarbons, halogenated hydrocarbons, alcohols, dihydric alcohols, polyhydric alcohols, ketones, esters, ethers, amides, acids, aldehydes, water, and mixtures thereof. 
     
     
         13 . A method according to  claim 1  wherein said liquid is water. 
     
     
         14 . A method according to  claim 1  wherein said liquid is selected from the group consisting of alcohols. 
     
     
         15 . A method according to  claim 1  wherein said foamable polymeric matieral precursor is substantially free of any surfactant-like molecules or polymers. 
     
     
         16 . A method according to  claim 1  wherein said foamed polymer is prepared by a process selected from the group consisting of extrusion, batch molding, and injection molding. 
     
     
         17 . A method according to  claim 1  wherein said foamable polymeric material precursor has cells that contain said blowing agent and/or said liquid. 
     
     
         18 . A method according to  claim 1  wherein said foamed polymer has cells that are of an average size less than 200 micrometers. 
     
     
         19 . A method according to  claim 1  wherein said foamed polymer has cells that are of an average size less than 10 micrometers. 
     
     
         20 . A method according to  claim 1  wherein said foamed polymer has cells that are of an average size less than 0.10 micrometers.